Updated as of the 18th of September 2015.
Choosing the right engine for your model might seem straightforward, but is not always as simple as peaking the cheapest offer on the web.
Jet models are meant to be flown and usually feature a fairly high wing loading ratio. The powerplant choice will significantly affect this ratio and might render a plane tricky to fly if not done properly. Consideration like price is also very important and must be integrated into the equation.
4. Go to the tables below by thrust segment and check the thrust-to-weight-to-price ratio.
5. Establish the following point: do I need a high quality engine to match a high quality airframe?
· Does this engine fit in the Airframe ?
. What is the service interval, is service provided locally ?
· What is the build quality/ reliability of the engine ?
· Is the idle thrust low enough for my plane ?
· What fuel/oil combination does it burn ?
7> Decide on the engine.
Also bear in mind that oversizing the engine for the airframe will cost you a lot more than picking up the right size. You'll see increased airframe an landing wear due to faster touchdown speeds and high impact energy as well as higher airframe stress in flight.
I have included a table listing the power to weight to price ratio for some engines available on the market. This is using web published manufacturer data, including price offered in the USA, updated as of June 2014, including the latest 200 N class engines announced.
I also included a new column in the table below, showing the thrust to weight ratio for each engine. Fuel efficiency, or TFSC is available on the RCJI table.
Below is the overall ranking for all the engines listed.
And then, the ranking by engine class.
Ranking for 210 N and above class.
Using the procedure described above and the tables will result in a wise and appropriate choice.